Smokeless boiler



` (No Model.) :PLUMMER 2 Sheets-Sheet V1. SMOKELBSS BOILER. No. 514,869.I i Patented Feb. 13, 1894.

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. v SMOKELESS BOILER.

No. 514,869. Patented Feb. 13, 1894.

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WILLIAM S. PLUMMEE, 0E sT. LOUIS, MISSOURI.

SMOKE'L-ESSBOILER.

SPECIFICATION forming part of Letters Patent No. 514,869, dated February 13, 1894.

Original application tiled February 6, 1893, Serial No. 461,090. Divided and this application tiled August 9, 1893. SerialNo. 482,779. (No model.)

To all whom it may concern:

Be it known that I, WILLIAM S. PLUMMER, of the city of St. Louis, State of Missouri, have invented certain new and useful Improvements in Smokeless Boiler-Furnaces, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part hereof.

My invention relates to smokeless furnaces of the class known as down-draft furnacesand it may be said to consist in a novel and peculiar combination and arrangement of both the up-draft fire-grate and the down-draft water-grate, particularly adapted for use under steam-boilers.

My invention consists further in certain details of construction, as will be herein fully set forth and pointed out in the claims.

This application is a division of a prior application for the same subject matter led by me February 6, 1893, Serial No. 461,090, allowed September 27, 1893.

In the drawings: Figure 1 is a sectional 1 side elevation of a`boilerfurnace embodying my invention. Fig. 2 is-a sectional front elevation with parts broken away. Fig. 3 is a p sectional transverse elevation of the same,

the section being taken on the line :1c-x of Fig. 1. Fig. 4 is a sectional plan view of the same, the section being taken'on the line Y-Y of Fig. 1. Fig. 5 is a similar view to the last, with the section taken on the line Z-Z of Fig. 1.

Referring again to thepdrawings: 1 indicates theV boiler or other object to be heated.

' The boiler has the usual horizontal iues 2 and smoke-cap or breeching 3 communicating with the chimney or smoke-stack connection 4.

5 indicates furnace walls, which, in the case of a horizontal steam-boiler, are the same as usual, with the exception of the bridge-wall and theV grate-setting and the bars near by the grates. I may state again that my invention contemplates a novel combination of a downdraft water-grate 6 and one or more up-draft fire-grates 7. (See Fig. 3.) These diiferent grates are relatively located with a series of solid grate-bars forming a separate'ire-'grate on each side of the water-grate. There is a single bridge-wall 8 over all the grates, and this is distinguished from the usual bridge- Awall in that it is fitted closely to the under side of Vthe boiler or otherobject to be heated, so as to prevent any passage of products of kcombustion between it and said object, or in loth er words, it has an imperforate surface above the grates, but it is arched or otherwise supported across the space beneath the object to be heated, and in a plane below the plane in which the grates are loc`atedso as 'to form what I term ahrc-passage 9 centrally beneath theimperforate portion of said bridgewall.

10 indicates an open space beneath the object to be heated, and in the rear of the grates,

which may be of any desired area and shape, to be determined by the arrangement of the Walls 5 and the floor of the furnace, the only essential construction being that said space or chamber lO be open at the top so as to expose theV boiler or thing to be heated to the kdirect action of the 4llames and heat issuing from saidl fire-passage 9 as is hereinafter stated.

The space beneath the grates, which would ,ordinarilyl correspond to the ash-pit ofl an ordinaryboiler furnace, is divided longitudinally into three separate chambers 11,12 and 13 respectively, which I denominate the two side ash-pits and the central combustion- Walls project upward in said combustionchamber a distance above the plane of the upper surface of said grates. The object of these low bridge-walls is to separate the gratey surface into three distinct portions veach eX- tending longitudinally of .the furnace, thus permitting each separate portion of the grate surface to be tired and cleaned separately and alternately without disturbing the re on IOC either of the remaining portions. These low longitudinal bridge-walls maybe dispensed with in some cases if desired, as their function is mainly to direct the iame and heat upward toward the thing to be heated, prior to its entrance into the central combustionchamber. The upper portions of these low bridge-walls are rounded or made apexial in form, as shown, so as to prevent the lodgment of ashes and cinders thereon.

Located above each of the side ash-pits 1l and 13 is a series of grate-bars of a common solid variety forming an up-draft fire-surface 7, and located above the central combustionchamber l2 is a series of tubes forming a down-draft fire-surface 6, at one side of each of said series of ordinary grate-bars. These grates are preferably constructed as here shown and described, but of course variations in them not amounting to inventionmay be made during the course of their construction and erection, without departing from my invention.

The central iresupporting surface is here shown as consisting of a series of tubes having cach end threaded or otherwise arranged and properly connected to a larger transverse tube 17 extending across the furnace and connected with the water or steam-space of the boiler.

I here show two large transverse tubes 17, one at the forward ends of the water-tubes 6 and one at their rear ends, and both connected to the water-space of the boiler by means of shorter vertical tubes 18, elbows 19, upper horizontal transverse tubes 20 and a threeway cast iron fitting 2l, the said three-way fitting having its upper surface of such a contour as to make a tight joint with the under side of the boiler, and all of which may be constructed by a skilled mechanic without further description. The short vertical tubes 18 and the transverse tubes 17, also the elbows 19 are located or incased in and surrounded by the material of which the front and bridge-walls are composed, to shield the same from the intense heat of the fire to which they would otherwise be exposed. (See Fig. 1.) It will be observed that the tubes 17 eX- tend completely across the furnace and are supported partially by the side-walls thereof.

From the above it will be seen that the water-tubed tire-surface is placed in communication with the waterspace of the boiler at each end of said ire-surface, and at different points upon the outer surface of the boiler, so that circulation of water therein may take place in either direction.

I may state that I have found it to be advantageous to inject the feed-water through the forward transverse tube 17, and for this purpose I have shown a suitable connection 22. (See Figs. 2 and 4.) The front of the furnace is fitted with a feed-door directly opposite each fire surface, and each of the ash-pits is provided with a door, all of which doors may be of common construction. By means of this arrangement each fire-surface may be separately supplied with fuel and cleaned independently of the others.

The method or mode of supplying fuel to the furnace will appear later on herein.

The operation is as follows: A fire is built in contact with all of the fire-surfaces and permitted to burn until glowing coals are produced thereon; then the side fire surfaces and the central fire-surface are supplied with fuel alternately, that is, so that there would be a glowing bed of coals upon the said central firesurface always when fresh fuel is thrown upon either of said side fire surfaces, and so that the smoke from said side fire surfaces will be caused to pass downward through said bed of glowing coals carried by said central surface, said central surface being supplied with fresh fuel at times when said side surfaces have located upon them, or one of them at least, a glowing bed of coals. It will thus-be observed that the central fire surface with its down-draft grate, acts not only to consume the smoke generated by itself, but it acts as a smoke-consumer for the products of coinbustion discharged by the fire surfaces located on each side and closely adjacent it, with the result that the smoke produced by all of the fire-surfaces, is consumed prior to its discharge into the smoke-stack or chimney of the furnace.

I do not broadly claim the construction of a down-draft grate located adjacent an updraft grate in the same furnace for I am aware that prior to my invention the same had been used, but in a different relative location from that which I herein show and claim; a single down-draft grate having been then arranged only in the rear of an up-draft grate.

What I claim is 1. A smoke consuming furnace having a single down-draft grate, and up-draft grates located on opposite sides of said down-draft grate, substantially as herein specified.

2. A smoke consuming furnace having a down-draft grate and up-draft grates located on opposite sides of said down-draft grate and each longitudinally of a single furnace and connected for operation, substantially as herein specified.

3. Theimprovedsmoke-consumingfurnace, constructed with a single down-draf t grate and two np-draft gratcs located one on each side of said down-draft grate and connected to discharge the products of combustion from the two side-grates down into and through the said down-draft grate, substantially as herein specified.

4. Theimproved smoke-consuming-furnace, constructed with two series of solid gratebars 7 arranged one series at one side of the furnace and another series at the opposite side of the furnace, each series forming a separate up-draft lire-supporting surface extending longitudinally of said furnace, a central flre-supporting surface 6 composed of hollow grate-bars or tubes and arranged IOO IIO

closely adjacent and between said side-grates and also extendinglongitudinally of the furnace, two transverse tubes 17 arranged one at the forward ends of the water-tubes 6 and one at the rear ends thereof and to which the ends of said water-tubes are connected, two horizontal transverse-tubes 2O located one above each of said transverse-tubes 17, short vertical tubes 18 and elbows 19 located in the Walls of the furnace and connecting said transverse-tubes 17 with said f transversetubes 20, and three-way cast iron fittings 21 applied to said tubes 20 and connecting the interior thereof with theinterior of the boiler at points separated a distance apart, substantially as herein specified. t

5. The improved smoke-consuming furnace, constructed with a bridge-Wall 8 fitted closely to the under side of the boiler so as to pre- Vent passage of products of combustion between itself and said boiler and supported across the space beneath said boiler to form a fire-passage 9 centrally beneath the said bridge-Wall and below the plane of the tiregrate, and one. beneath each of said side- 35 plates, said central-chamber being connected withY the said central passage 9 beneath said bridge-Wall a feed door opposite each grate, a door for each of said` chambers and connections between said passage 9 and a chimney or stack, substantially as herein specified.

In testimony whereof I affix my signature in presence of two witnesses.

WILLIAM S. PLUMMER.

Witnesses:

A. A. BLANKEMMISTER, JNO. C. HIGDON. 

